With technological advances, portable terminals such as a mobile phone, a PDA, and PMP, a navigation system, and a laptop are equipped to additionally provide a local communication functions between devices such as DMB, wireless internet, in addition to basic functions such as calling, playing video/music, and navigation. Accordingly, portable terminals are equipped with a plurality of antennas for wireless communication such as wireless internet and Bluetooth.
Further, recently, functions such as information exchange between terminals, settlement, ticket advance purchase, and searching using local communication (that is, NFC) are applied to portable terminals. To this end, portable terminals are equipped with an antenna module (that is, NFC antenna module) used in for local communication. The NFC antenna module is a non-contact local wireless communication module, which is an RFID using a frequency band of about 13.56 Hz, and transmits data between terminals at a short distance about 10 cm. NFC is used in various areas such as transmission of product information at a supermarket or a store or transmission of travel information of visitors, traffic, access control, and a locking system, in addition to payment.
In general, NFC antenna modules are formed flat and mounted on a battery pack and a battery cover, etc. That is, NFC antenna modules are designed to communicate with NFC antenna modules in other electronic devices by forming a radiation field toward the rear side of portable terminals for convenience for users and structural features.
However, recently, the rear covers of portable terminals are increasingly made of metal, so the performance of built-in antennas such as the NFC antenna is deteriorated.
To solve this problem in the related art, the portions around a camera and a flash in those metallic rear covers have been made of non-metallic materials and then an antenna has been mounted.
However, since the non-metallic area for mounting an antenna is small and surrounded by metal, there is still a problem that the performance of the antenna is deteriorated.